Hi peiyouliao,
I have inspected your site and it seems like the module's css file is rendered by pagespeed. Here is my screenshot:
http://screencast.com/t/hjV0Etrw . Can you try turn it off and test this again.
By the way, I suspected that it might be coming from your template. Can you try change the template to the default Joomla template to test this. Please clean your site and browser cache after changing the template.
Regarding this issue,
I found that if the outside of Easysocial page
Easysocial displayed module is not correct, how do I displayed the module correctly?
I unable to replicate this issue locally. EasySocial user module is displaying correctly on my local.
Please advise.